Almost done squeezing out ponies… What else can I do that would give me any worthwhile gains, besides going FI?

2005 AT With 5/16 Plenum Spacer, Z-Tube, HKS Cat Back, and a Up-Rev Tune.

 

Short of cams and long tube headers with no cats, that's about it.

 

Yeah I was thinking that was about it. Not going to bother with long tubes and no cats, California doesn't like that and I am not going to take them off and on for each smog.

I think it might be time to trade up to a G37... Definitely going with a coupe this time.

I assume the G37's are similar when it comes to squeezing out ponies?

 

You can free up HP by getting a light weight pulley and a CF driveshaft or aluminum driveshaft

 

Yeah, it reduces "rotational mass" and lets your engine rev free. I have the light weight FW and I can deff tell the diff. You have to put up with the chatter at idle, however.

 

The G37 has even less options cuz things like the plenum design were fixed.

Your next step, as has been mentioned, should be rotational mass lightening. Lightweight clutch/flywheel, lightweight crank pulley (some controversy here), lightweight wheels (18s for best weight/gearing), driveshaft, rotors. All those things will help it use your HP much more efficiently. Also, chassis bracing helps put that power straight to the ground.

Also, lightening the car in general helps you feel the HP the way you want it to. Every 100lbs you take off is worth 1/10 of a second in your 1/4 mile. It wouldn't be terribly hard to take 200+ lbs off the car.

Final drive ratio can be changed too and that'll really help you feel a lot more power.

 

Thanks for all the replies and advice...

I think I will leave the sedan where it is at now and go buy a coupe; I would rather spend those mods time and money on a Coupe with a RevUp motor and a MT versus trying to beef up a sedan.

Now I just have to decide if I want to go with a 35 or 37.

 

If you look at the lbs. per hp ratio the 37 has got to feel faster.

 

No, because the TQ is the same as the VQ35DE (270ft/lb) and TQ is what you feel at launch. TQ is a MUCH more accurate way of measuring actual power, and HP is a marketing scheme. The HP suggests the 37 would be slightly less anemic at higher speeds, but the 37 is negligibly faster than the 35. Almost immeasurably stock for stock.

 

A G37 is noticeably faster than the G35, stock for stock. Power-to-weight ratio is just part of the puzzle. You also need to look at the transmission and final drive gearing, where the power bands of the engines are and how they are tuned........etc. I'm sure Jairen on here would love to share his experience comparing a G37 7AT to his 05 6MT while at the tracks.

 

Whosurbuddy, help me out here.

 

kudos on deciding to get a coupe! who mods a sedan anyway???

 

Honestly, without FI, you are pretty much done. There are no worthwhile gains past I/E/T, unless you go big money on cams/longtubes. You could get lightweight wheels and it would feel a bit quicker.

If I were you, I would stop throwing money away on any more bolt-on mods and start saving up for FI or a better car.

 

the #1 go to in my book. get a better diff. takes huge chunks off the 1/4. but your mileage will suffer.

your on the 3.5 rear end ? 4.0x is the lats thing you should do besides basic weight loss.

 

Both the 35 and 37 are pretty much maxed out as it is. Hate to say it but the G35/37 platform is one expensive car to modify in terms of bang for your buck. If you want significant gains, you'll need to look into FI.

With the 3.5L being 8 years old now, i'd look into a G37.